17 yr old daughter starting to act out

We have been a stable family...married almost 23 years. Three daughters 20 (college) 17 1/2 (high school senior) and 5 year old.

We have really never had any major problems or issues with the girls. Little things here and there. Our oldest is very school/career oriented and always has been. Hard worker, very good student, very involved. However she has gotten into trouble. When she was in high school and working at a local business at night - she one time snuck out late and drove to her boyfriends house to give him a present and I found that she was not home - called her which made her speed home and get a ticket) She lied to us and got a ticket - but I get that kids are going to do stupid things sometimes.

Our middle daughter has always been materialistic (we have never handed her anything on a platter).
We preach hard work and respect all the time. She is more street smart than book smart. We believe if she puts her mind to it - she could be an honor roll student - however she has maintained merit roll status. Mostly a B student. She says that she wants to go to college. We have not pressured her to do that. I tried to gear her toward a community college - but she really wants to go away (about an hour and half away) and was accepted. We were thrilled.

She recently started working during the end of her senior year. A job she seems to like and she makes good money. She was very excited about concerts she was going to go to, grad parties etc. Her prom was two weeks ago. The day after her prom she drove out to a picnic prom party and was stopped for speeding. She immediately called me to tell me. My husband and I were disappointed but understood and did not freak out.

Well then - last night - I got a call from the local Sheriff's office that they have her there because she was picked up for shoplifting. She was out shopping for things to go to a concert and tried shoplifting two bathing suit tops.

Needless to say I am beyond disappointed. I am hurt and sad. My husband has not even spoken to her yet. However we told her that her phone is gone, computer is gone, concert is gone, she goes to school and to work and that is it. No parties, no friend's houses....and she has to write a letter of apology to the store.

She still has to go get fingerprinted and get her mug shot and then go to court. I told her that she needs to do these things herself as my husband and I both work. I just don't get it. I don't understand why - when this was going to be "HER" summer of fun.....why would she be acting out like this.

I can't talk to her. I try - but she has never been much of a talker - wants to figure things out herself. But as odd as it sounds, I do consider us close. I just have knots in my stomach.

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